chdkfandomcom-20200222-history
Obtaining a firmware dump
Cameras overview ;DIGIC II :Axxx: A410, A430, A460, A530, A540, A550, , , , , , :Sx IS: , :Sxx: :SDxx: SD30 :SDxxx(IXUS): SD200, SD300, SD400, SD430, SD450, SD500, SD550, SD600, SD630, SD700IS ;DIGIC III :Axxx: A560, A570IS :Sx IS: S5IS :SDxx: SD40 :SDxxx(IXUS): SD750, SD800IS, SD850IS, SD900, SD1000 :Gx: G7 ;Legend: :* Black - neither original firmware nor firmware dump is available :* - either original firmware or firmware dump is available; porting is needed :* - successfully ported Q. What are the necessary steps to port the CHDK firmware on a DIGIC II cam which is currently not supported? A. Here is a basic description to give you an idea of the procedure. For more detailed explanations see the links below, especially this one. * First you need either the original firmware or a firmware dump of your camera. : The firmware dump can be obtained with a special firmware dumper which has to be adjusted for your camera. :It is a firmware update file where one of the files inside (WriterInFIR.bin) has been patched in a way that it will make a memory dump onto the SD card. Usually this is possible if another platform-dependant code is disabled (this includes but is not limited to: LCD, LEDs, sound). * Create a platform subdirectory for a new camera model/fw version (you can just copy an existing one). * Find the adresses of the RAW-, video- and frame-buffers. * Modify a couple of addresses and constants. * Check the keyboard "driver" (button constants and behaviour). * Check the addresses of autofound functions. Manually correct/find the right addresses for some of them with a disassembler like IDA Pro. Q. How can I get a firmware dump? A. There are two ways known now: Software method The method is to make/adapt the WIF loader from original firmware update to similar camera models. As this loader has the functions to work with files, this way allow to just save a dump of original firmware to SD-card. The main problem of this method using is you have to pass all initialization stages of original firmware in order to be able to write to flash card. ;Firmwares were gotten by this method : A620, A630, A640, A710, S2IS, S3IS :: Are the firmware dumpers for these models available? So one could start right ahead hacking away with these firmwares, and to have an example for new models. Thanks very much, PTT 02:08, 9 July 2007 (UTC) :::There is the binary for A610e - http://vitalyb.mail333.com/a610/dump/ (I don't have sources). Also there is source code of S2/S3 dumper - http://grandag.nm.ru/hdk/dumper/ . But I did not look into it. --GrAnd 14:31, 9 July 2007 (UTC) Hardware-software solution This method is based on the 'blinking' of the original firmware through a led of the camera. You have to make a receiver (photodiode or phototransistor), the software to write a dump, decoder and a tiny firmware which outputs its firmware trough led. The receiver can be connected to serial port (you need to emulate the UART in the camera in this case) or to microphone input. I used the microphone input. All necessary files (with sources) you can get here. The scheme I used: / \ | | \ / +-----------+ + + | | |----\ | |-------+ ----*------------| | | | ----*---------------| | | | | |----/ | |----------------+ | | phototransistor + + BPW96C or analog | | 3.5mm plug to mic-in of soundcard The transmitting protocol * Header (3600 bytes) - "0123456789" sequence for visual control of data. * Blocks - 4096 blocks of 1K data :* Address (4 bytes) - address of the current block :* Data (1024 bytes) - piece of firmware :* CRC16 x 2 (4 bytes) - CRC16 of block (repeated twice) Each byte is encoded in the following way: ,where: # Spacing between bytes # Spacing between bits # Wide pulse - logical "1" # Narrow pulse - logical "0" The usage flow: * Connect the receiver to the microphone input of sound card. * Run a recording application (I used Adobe Audition) with the following parameters: 96KHz (it's adjustable), 8 bit, mono. * Direct 'blinking' led to the receiver. * Start the recording. Start the 'blinking' firmware. * Wait for process is finished (1-7 hours depends on speed chosen). The camera will be switched off at the end. * Save the data to the PCM-file (8-bit unsigned raw data, not WAV!). * Process the file by 'adc.exe '. You will get 'dump'-file. * Run 'dec.exe'. You will get 'dump.dat'-file. This file is the firmware. Speed/signal adjusting: I may be required to some adjustments in depend on camera/led/receiver used. The main idea to get 'readable' signal as shown on the picture above. Here the values for certain speeds and leds for A610. A610 - AF beam, FAST (9230 bod) 96KHz -------------------------- fw: #define DELAY_SYNC 45 #define DELAY_SPACE 50 #define DELAY0 1 #define DELAY1 25 decode: #define LEVEL_THRES_HI 0xA0 #define LEVEL_THRES_LO 0x80 #define LEN_SYNC 5 #define LEN_SPACE 1 #define LEN_0 1 #define LEN_1 6 A610 - AF beam, SLOW (2500 bod ) 96KHz ------------------------- fw: #define DELAY_SYNC 400 #define DELAY_SPACE 100 #define DELAY0 100 #define DELAY1 200 decode: #define LEVEL_THRES_HI 0xA0 #define LEVEL_THRES_LO 0x80 #define LEN_SYNC 40 #define LEN_SPACE 5 #define LEN_0 12 #define LEN_1 24 A610 - BLUE_led (1600 bod) 11KHz ------------------------- fw: #define DELAY_SYNC 400 #define DELAY_SPACE 175 #define DELAY0 150 #define DELAY1 350 decode: #define LEVEL_THRES_HI 0x90 #define LEVEL_THRES_LO 0x70 #define LEN_SYNC 7 #define LEN_SPACE 1 #define LEN_0 1 #define LEN_1 4 ;Firmwares were gotten by this method : A610, A700 Links Instruction Vitaly's FAQ Compiling CHDK under Linux List of Property Cases List of Property Cases porting the CHDK